When the time comes to replace your furnace, you'll want to make sure the entire installation process goes as smoothly as possible. Nevertheless, there are plenty of pitfalls that could trip up your furnace installation, resulting in time-consuming and potentially expensive delays. To keep this from happening to you, you'll want to avoid the following installation mistakes:

Mistake #1: Doing it Alone

You may be a natural when it comes to most do-it-yourself tasks, but installing a new furnace is one of those jobs where DIY enthusiasm takes a backseat to professional experience. Your HVAC contractor has years of experience handling heating and cooling system installations and repairs, along with a plethora of technical expertise for solving both common and uncommon installation problems. If you run into an issue during your furnace installation, you may not have the knowledge or the equipment to make whatever corrections are needed.

There's another reason why you should leave your furnace installation to the pros: the professionals are able to guarantee their work. Not only can you rest easier knowing that the job was done right the first time, but you can also call on your HVAC contractor if any warranty-related issues pop up beyond the installation.

Mistake #2: Going Over or Under on Furnace Size

There's a good reason why your HVAC contractor takes great strides in calculating your heating system's appropriate size. It's easy to overestimate or underestimate how much heating capacity is needed to keep a building warm. Stepping up to a larger furnace can warm your spaces faster, but you'll waste energy, invite heavier wear and tear on your heating equipment and eventually be faced with yet another furnace replacement after only a few years of service.

Downsizing your furnace may initially save you money, but you'll end up running your furnace constantly just to keep up with heating demands. This also places unnecessary wear and tear on your heating equipment, resulting in a furnace that's worn out long before its time.

Instead of going over or under on the size of your new furnace, you should always aim for the sweet spot. Your HVAC contractor can help you find the appropriate sized furnace for your heating needs.

Mistake #3: Getting the Exhaust Wrong

Unfortunately, it's all too easy to get your new furnace's exhaust set up all wrong. For starters, the type of exhaust system needed for your furnace depends heavily on the type of furnace you purchase and install. Using the wrong type of exhaust ventilation for your furnace could have severe consequences. At best, it could negatively impact your furnace's energy efficiency. At worst, it could allow carbon monoxide (CO) and other poisonous gases to reenter the furnace and spread indoors.

Proper furnace exhaust design is essential for maintaining a safe and reliable heating system. You should work with your HVAC contractor to avoid any pitfalls or compromises that could jeopardize the safety of your furnace.

Mistake #4: Skimping on the Drainage System

Today's high-efficiency furnaces are designed to extract as much energy as possible from the fuel they use. As a result, your new furnace may produce large quantities of wastewater that has to be drained properly. Without a properly-designed drain system, your new furnace could end up wet in short order. Poor drainage can cause large amounts of wastewater flooding, which in turn exposes your furnace to mold and mildew buildup and corrosion damage. If temperatures drop below freezing, the wastewater stuck in your pipes could freeze and expand, resulting in large-scale damage throughout your drainage system.

If you plan on installing a high-efficiency furnace, you'll need to upgrade or at least reevaluate your current drainage system. This way, you can avoid the significant water damage that may result from using inadequate drainage for brand-new heating system.